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1.
Biochem Biophys Res Commun ; 720: 150065, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38749188

RESUMO

Neovascular eye diseases, including proliferative diabetic retinopathy and retinopathy of prematurity, is a major cause of blindness. Laser ablation and intravitreal anti-VEGF injection have shown their limitations in treatment of retinal neovascularization. Identification of a new therapeutic strategies is in urgent need. Our study aims to assess the effects of Cryptotanshinone (CPT), a natural compound derived from Salvia miltiorrhiza Bunge, in retina neovascularization and explore its potential mechanism. Our study demonstrated that CPT did not cause retina tissue toxicity at the tested concentrations. Intravitreal injections of CPT reduced pathological angiogenesis and promoted physical angiogenesis in oxygen-induced retinopathy (OIR) model. CPT improve visual function in OIR mice and reduced cell apoptosis. Moreover, we also revealed that CPT diminishes the expression of inflammatory cytokines in the OIR retina. In vitro, the administration of CPT effectively inhibited endothelial cells proliferation, migration, sprouting, and tube formation induced by the stimulation of human retinal vascular endothelial cells (HRVECs) with VEGF165. Mechanistically, CPT blocking the phosphorylation of VEGFR2 and downstream targeting pathway. After all, the findings demonstrated that CPT exhibits potent anti-angiogenic and anti-inflammatory effects in OIR mice, and it has therapeutic potential for the treatment of neovascular retinal diseases.


Assuntos
Injeções Intravítreas , Camundongos Endogâmicos C57BL , Fenantrenos , Neovascularização Retiniana , Animais , Fenantrenos/farmacologia , Fenantrenos/administração & dosagem , Neovascularização Retiniana/tratamento farmacológico , Neovascularização Retiniana/patologia , Neovascularização Retiniana/metabolismo , Humanos , Camundongos , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/patologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-39205642

RESUMO

Transcription factor 3 (TCF3), a pivotal member of the TCF/LEF family, plays a critical role in tumorigenesis. Nonetheless, its impact on the tumor microenvironment (TME) and cancer phenotypes remains elusive. We perform an exhaustive analysis of TCF3 expression, DNA variation profiles, prognostic implications, and associations with the TME and immunological aspects. This study is based on a large-scale pan-cancer cohort, encompassing over 17,000 cancer patients from multiple independent datasets, validated by in vitro assays. Our results show that TCF3/4/7 exhibits differential expression patterns between normal and tumor tissues across pan-cancer analyses. Mutational analysis of TCF3 across diverse cancer types reveals the highest alteration rates in biliary tract cancer. Additionally, mutations and single nucleotide variants in TCF3/4/7 are found to exert varied effects on patient prognosis. Importantly, TCF3 emerges as a robust predictor of survival across all cancer cohorts and among patients receiving immune checkpoint inhibitors. Elevated TCF3 expression is correlated with more aggressive cancer subtypes, as validated by immunohistochemistry and diverse cohort data. Furthermore, TCF3 expression is positively correlated with intratumoral heterogeneity and angiogenesis. In vitro investigations demonstrate that TCF3 is involved in epithelial-mesenchymal transition, migration, invasion, and angiogenesis. These effects are likely mediated through the interaction of TCF3 with the NF-κB/MMP2 pathway, which is modulated by IL-17A in human uveal melanoma MUM2B cells. This study elucidates, for the first time, the significant associations of TCF3 with DNA variation profiles, prognostic outcomes, and the TME in multiple cancer contexts. TCF3 holds promise as a molecular marker for diagnosis and as a potential target for novel therapeutic strategies, particularly in uveal melanoma.

3.
J Cell Biochem ; 120(11): 19202-19214, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31270856

RESUMO

Uveal melanoma (UVM) is an adult intraocular malignancy which is the most frequent and has a high tendency for metastasis. This study aims to develop significant differential gene subnetwork between primary and metastatic UVM to identify potential prognostic biomarkers. Differentially expressed genes (DEGs) among three chip datasets were downloaded from Gene Expression Omnibus and identified according to standardization annotation information. Genetic enrichment analyses were utilized to describe biologic functions. The protein-protein interaction network of DEGs was developed and the module analysis was constructed by STRING and Cytoscape. Kaplan-Meier method of the integrated expression score was applied to analyze survival outcomes. Functional annotation was assessed to perform GO and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. In addition, ClueGO and gene set enrichment analysis were analyzed to detect underlying significant genes and involved signaling pathways. A total of 103 DEGs with function enrichment were recognized and might be considered as candidate prognostic biomarkers between primary and metastatic UVM. Furthermore, Kaplan-Meier method suggested that SCD5, SPTBN1, FABP5, SQLE, PTPLA (HACD1), and CDC25B were independent prognostic factors in UVM. Functional annotations indicated that the most involved significant pathways including interferon-gamma response, IL-6 JAK STAT3 signaling, TNFA signaling via NFKB and inflammatory response. Significant DEGs between primary and metastatic UVM tissue were identified and might have involved in the metastasis of UVM. SCD5, SPTBN1, FABP5, SQLE, PTPLA (HACD1), and CDC25B transcription levels were of high prognostic value, which might assist us to understand the underlying carcinogenesis or advancement of UVM better.


Assuntos
Biomarcadores Tumorais , Bases de Dados de Ácidos Nucleicos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Melanoma , Mapas de Interação de Proteínas , Neoplasias Uveais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Anotação de Sequência Molecular , Metástase Neoplásica , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia
4.
Cell Mol Gastroenterol Hepatol ; 17(1): 149-169, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37717824

RESUMO

BACKGROUND & AIMS: Hepatic ischemia-reperfusion injury is a significant complication of partial hepatic resection and liver transplantation, impacting the prognosis of patients undergoing liver surgery. The protein proprotein convertase subtilisin/kexin type 9 (PCSK9) is primarily synthesized by hepatocytes and has been implicated in myocardial ischemic diseases. However, the role of PCSK9 in hepatic ischemia-reperfusion injury remains unclear. This study aims to investigate the role and mechanism of PCSK9 in hepatic ischemia-reperfusion injury. METHODS: We first examined the expression of PCSK9 in mouse warm ischemia-reperfusion models and AML12 cells subjected to hypoxia/reoxygenation. Subsequently, we explored the impact of PCSK9 on liver ischemia-reperfusion injury by assessing mitochondrial damage and the resulting inflammatory response. RESULTS: Our findings reveal that PCSK9 is up-regulated in response to ischemia-reperfusion injury and exacerbates hepatic ischemia-reperfusion injury. Blocking PCSK9 can alleviate hepatocyte mitochondrial damage and the consequent inflammatory response mediated by ischemia-reperfusion. Mechanistically, this protective effect is dependent on mitophagy. CONCLUSIONS: Inhibiting PCSK9 in hepatocytes attenuates the inflammatory responses triggered by reactive oxygen species and mitochondrial DNA by promoting PINK1-Parkin-mediated mitophagy. This, in turn, ameliorates hepatic ischemia-reperfusion injury.


Assuntos
Hepatopatias , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Hepatócitos/metabolismo , Mitofagia/genética , Pró-Proteína Convertase 9 , Proteínas Quinases/genética , Traumatismo por Reperfusão/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
5.
Adv Pharm Bull ; 14(2): 469-482, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39206403

RESUMO

Purpose: Neovascular age-related macular degeneration (nAMD) is a prevalent cause of blindness in the elderly. Standard treatment includes anti-vascular endothelial growth factor (anti-VEGF) drugs, such as aflibercept. However, anti-VEGF drugs may have limited efficacy and cause drug resistance. This study explores whether Kavain, an anti-inflammatory molecule from Piper methysticum, can treat choroidal neovascularization (CNV). Methods: Various experiments were conducted to assess the Kavain's toxicity. The impact of Kavain on in vitro cultured endothelial cells was examined through 5-ethynyl-20-deoxyuridine (EdU) assays, transwell migration assays, and tube formation assays. The therapeutic effects of Kavain on CNV were investigated using a laser-induced CNV mice model. To elucidate the mechanism of Kavain, network pharmacology analysis, molecular docking, and western blots were performed. Results: Kavain exhibited no apparent toxicity both in vitro and in vivo. Kavain significantly decreased endothelial cell viability, proliferation, migration, and tube formation ability in a dose-dependent manner compared to the hypoxia groups (P<0.05). Kavain alleviated CNV in the laser-induced CNV mouse model compared to the control groups (P<0.05). These effects were statistically significantly enhanced in the Kavain plus aflibercept groups (P<0.05). Following Kavain administration, the expression levels of various inflammatory factors were markedly reduced in retinal pigment epithelium (RPE)/choroid complexes (P<0.05). Mechanistically, Kavain decreased the activity of the hypoxia-inducible factor 1α (HIF-1α)/VEGF-A/ VEGF receptor 2 (VEGFR2) signaling pathway. Conclusion: Our study is the first to demonstrate Kavain's potential as a promising treatment for nAMD, owing to its dual effects of anti-inflammation and anti-angiogenesis.

6.
Int J Nanomedicine ; 18: 437-453, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36718193

RESUMO

Background: Ocular vascular diseases are the major causes of visual impairment, which are characterized by retinal vascular dysfunction and robust inflammatory responses. Traditional anti-angiogenic or anti-inflammatory drugs still have limitations due to the short-acting effects. To improve the anti-angiogenic or anti-inflammatory efficiency, a dual-drug nanocomposite formulation was proposed for combined anti-angiogenic and anti-inflammatory treatment of ocular vascular diseases. Methods : CBC-MCC@hMSN(SM) complex nanoformulation was prepared by integrating conbercept (CBC, an anti-angiogenic drug) and MCC950 (MCC, an inhibitor of inflammation) into the surface-modified hollow mesoporous silica nanoparticles (hMSN(SM)). CBC-MCC@hMSN(SM) complex nanoformulation was then characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, zeta potentials, and nitrogen adsorption-desorption measurement. CBC and MCC release profile, cytotoxicity, tissue toxicity, anti-angiogenic effects, and anti-inflammatory effects of CBC-MCC@hMSN(SM) were estimated using the in vitro and in vivo experiments. Results:  CBC-MCC@hMSN(SM) complex had no obvious cytotoxicity and tissue toxicity and did not cause a detectable ocular inflammatory responses. CBC-MCC@hMSN(SM) complex was more effective than free CBC or MCC in suppressing endothelial angiogenic effects and inflammatory responses in vitro. A single intraocular injection of CBC-MCC@hMSN(SM) complex potently suppressed diabetes-induced retinal vascular dysfunction, choroidal neovascularization, and inflammatory responses for up to 6 months. Conclusion : Combined CBC and MCC nanoformulation provides a promising strategy for sustained suppression of pathological angiogenesis and inflammatory responses to improve the treatment outcomes of ocular vascular diseases.


Assuntos
Oftalmopatias , Doenças Vasculares , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia
7.
Medicine (Baltimore) ; 102(24): e34043, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327269

RESUMO

BACKGROUND: Adeno-associated virus (AAV) plays a vital role in ocular gene therapy and has been widely studied since 1996. This study summarizes and explores the publication outputs and future research trends of AAV-based ocular gene therapy. METHODS: Publications and data about AAV-based ocular gene therapy were downloaded from the Web of Science Core Collection or ClinicalTrials.gov database. The publications and data were analyzed by Microsoft Excel, CiteSpace, VOS viewer, and a free online platform (http://bibliometric.com). RESULTS: Totally 832 publications from the Web of Science Core Collection relevant to AAV-based ocular gene therapy were published from 1996 to 2022. These publications were contributed by research institutes from 42 countries or regions. The US contributed the most publications among these countries or regions, notably the University of Florida. Hauswirth WW was the most productive author. "Efficacy" and "safety" are the main focus areas for future research according to the references and keywords analysis. Eighty clinical trials examined AAV-based ocular gene therapy were registered on ClinicalTrials.Gov. Institutes from the US and European did the dominant number or the large proportion of the trials. CONCLUSIONS: The research focus of the AAV-based ocular gene therapy has transitioned from the study in biological theory to clinical trialing. The AAV-based gene therapy is not limited to inherited retinal diseases but various ocular diseases.


Assuntos
Dependovirus , Face , Humanos , Dependovirus/genética , Retina , Bibliometria , Terapia Genética
8.
Circulation ; 120(12): 1056-64, 2009 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-19738141

RESUMO

BACKGROUND: Blood lead concentration has been associated with mortality from different causes in several studies. Many effects of lead exposure that might increase risk of death are likely to result from cumulative exposure, for which bone lead is a better biomarker than blood lead. The association between bone lead levels and mortality has not been explored. METHODS AND RESULTS: We prospectively assessed the association between both blood lead and bone lead, analyzed with the use of K-shell x-ray fluorescence, and mortality among 868 men in the Normative Aging Study. We identified 241 deaths over an average of 8.9 (SD=3.9) years of follow-up. We calculated adjusted hazard ratios and 95% confidence intervals using Cox proportional hazards. Compared with the lowest tertile of patella bone lead, the fully adjusted hazard ratios in the highest tertile for all-cause and cardiovascular mortality (n=137 deaths) were 2.52 (95% confidence interval, 1.17 to 5.41) and 5.63 (95% confidence interval, 1.73 to 18.3), respectively. The age-, smoking-, and race-adjusted hazard ratio for ischemic heart disease mortality (n=62 deaths) in the highest tertile was 8.37 (95% confidence interval, 1.29 to 54.4). Results were similar for tibia lead. Bone lead was not associated with cancer, and blood lead was not associated with any mortality category. CONCLUSIONS: We found bone lead to be associated with all-cause and cardiovascular mortality in an environmentally exposed population with low blood lead levels. This study suggests that cumulative lead exposure from prior decades of high environmental exposures continues to significantly affect risk of death despite recent declines in environmental lead exposure.


Assuntos
Osso e Ossos/química , Doenças Cardiovasculares/mortalidade , Chumbo/toxicidade , Neoplasias/mortalidade , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Causas de Morte , Exposição Ambiental , Humanos , Chumbo/análise , Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos
9.
Phys Med Biol ; 54(4): 963-79, 2009 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-19147899

RESUMO

A Monte Carlo simulation of repeated cubic units representing trabecular bone cavities in adult bone was employed to determine absorbed dose fractions evaluated for (3)H, (14)C and a set of alpha-emitters incorporated within a bone remodeling compartment (BRC). The BRC consists of a well-oxygenated vascular microenvironment located within a canopy of bone-lining cells. The International Commission on Radiological Protection (ICRP) considers that an important target for radiation-induced bone cancer is the endosteum marrow layer adjacent to bone surface where quiescent bone stem cells reside. It is proposed that the active stem cells and progenitor cells located above the BRC canopy, the 'BRC stem cell niche', is a more important radiation-induced cancer target volume. Simulation results from a static model, where no remodeling occurs, indicate that the mean dose from bone and bone surface to the 50 microm quiescent bone stem cell niche, the current ICRP target, was substantially lower (two to three times lower) than that to the narrower and hypoxic 10 microm endosteum for (3)H, (14)C and alpha-particles with energy range 0.5-10 MeV. The results from a dynamic model indicate that the temporal alpha-radiation dose to active stem/progenitor cells located in the BRC stem cell niche from the material incorporated in and buried by forming bone was 9- to 111-fold greater than the dose to the quiescent bone stem cell niche. This work indicates that the remodeling portion of the bone surface, rather than the quiescent (endosteal) surface, has the greatest risk of radiation-induced bone cancer, particularly from short-range radiation, due to the elevated dose and the radiosensitizing oxygen effect.


Assuntos
Remodelação Óssea/fisiologia , Remodelação Óssea/efeitos da radiação , Osso e Ossos/fisiologia , Osso e Ossos/efeitos da radiação , Radioisótopos de Carbono , Deutério , Células-Tronco Hematopoéticas/fisiologia , Células-Tronco Hematopoéticas/efeitos da radiação , Modelos Biológicos , Eficiência Biológica Relativa , Partículas alfa , Simulação por Computador , Relação Dose-Resposta à Radiação , Humanos , Doses de Radiação
10.
Biochim Biophys Acta ; 1770(8): 1169-80, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17570595

RESUMO

Trichosanthin (TCS), a traditional Chinese medicine, exerts antitumor activities by inducing apoptosis in many different tumor cell lines. However, the mechanisms remain obscure. The present study focused on various caspase pathways that may be involved in TCS-induced apoptosis in leukemia HL-60 cells. Key caspases in both intrinsic and extrinsic pathways including caspase-8, -9 and -3 were activated upon TCS treatment. Additionally, TCS treatment induced upregulation of BiP and CHOP and also activated caspase-4, which for the first time strongly supported the involvement of endoplasmic reticulum stress pathway in TCS-induced apoptosis. Interestingly, although caspase-8 was activated, Fas/Fas ligand pathway was not involved as evidenced by a lack of induction of Fas or Fas ligand and a lack of inhibitory effect of anti-Fas blocking antibody on TCS-induced apoptosis. Instead, caspase-8 was activated in a caspase-9 and -4 dependent manner. The involvement of mitochondria was demonstrated by the reduction of mitochondrial membrane potential and release of cytochrome c and Smac besides the activation of caspase-9. Further investigation confirmed that caspase-3 was the major executioner caspase downstream to caspase-9, -4 and -8. Taken together, our results suggested that TCS-induced apoptosis in HL-60 cells was mainly mediated by mitochondrial and ER stress signaling pathways via caspase-3.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais , Tricosantina/farmacologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Caspases Iniciadoras , Relação Dose-Resposta a Droga , Chaperona BiP do Retículo Endoplasmático , Ativação Enzimática/efeitos dos fármacos , Células HL-60 , Proteínas de Choque Térmico/metabolismo , Humanos , Potenciais da Membrana/efeitos dos fármacos , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Transcrição CHOP/metabolismo
11.
Biochim Biophys Acta ; 1770(1): 63-70, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16949756

RESUMO

Trichosanthin (TCS), a type I ribosome-inactivating protein, induces cell death in various cell types including several tumor cell lines. However, the mechanism remains largely uncharacterized. In this study, we investigated the possible mechanism underlying its cytotoxicity by using human chronic myeloid leukemia cell line K562. We found that TCS induced apoptosis in K562 cells in a time- and concentration-dependent manner and can be blocked by caspase-3 inhibitors. Interestingly, TCS treatment induced a transient elevation in intracellular calcium concentration and a slow increase in reactive oxygen species production, while calcium chelators and antioxidants had no obvious effect on TCS-induced apoptosis, suggesting that calcium changes and reactive oxygen species may not be involved in TCS-mediated apoptosis in K562 cells. Instead we found that TCS partly inhibited PKC activity. Indeed, the PKC activator, PMA, inhibited while the PKC inhibitor, calphostin c, enhanced TCS-induced apoptosis. These PKC modulators had similar effects on TCS-induced cleavage of caspase-3, and caspase-3 inhibitors prevented calphostin c-enhanced apoptosis induced by TCS. In summary, we conclude that TCS induces apoptosis in K562 cells partly via PKC inhibition and caspase-3 activation.


Assuntos
Apoptose/efeitos dos fármacos , Naftalenos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Tricosantina/farmacologia , Cálcio/metabolismo , Sinalização do Cálcio , Caspase 3/metabolismo , Citometria de Fluxo , Humanos , Microscopia Confocal , Espécies Reativas de Oxigênio
12.
Am J Epidemiol ; 166(12): 1400-8, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17823382

RESUMO

The authors evaluated the association between lead burden and psychiatric symptoms and its potential modification by a delta-aminolevulinic acid dehydratase (ALAD) polymorphism. Lead measurements in blood or bone and self-reported ratings on the Brief Symptom Inventory from 1991 to 2002 were available for 1,075 US men participating in the Department of Veterans Affairs (VA) Normative Aging Study. The authors estimated the prevalence odds ratio for the association between interquartile-range lead and abnormal symptom score, adjusting for potential confounders. An interquartile increment in tibia lead (14 microg/g) was associated with 21% higher odds of somatization (95% confidence interval of the odds ratio: 1.01, 1.46). An interquartile increment in patella lead (20 microg/g) corresponded to a 23% increase in the odds of global distress (95% confidence interval of the odds ratio: 1.02, 1.47). An interquartile increment in blood lead (2.8 microg/dl) was associated with 14% higher odds of hostility (95% confidence interval of the odds ratio: 1.02, 1.27). In all other analyses, lead was nonsignificantly associated with psychiatric symptoms. The adverse association of lead with abnormal mood scores was generally stronger among ALAD 1-1 carriers than 1-2/2-2 carriers, particularly regarding phobic anxiety symptoms (p(interaction) = 0.004). These results augment evidence of a deleterious association between lead and psychiatric symptoms.


Assuntos
Intoxicação do Sistema Nervoso por Chumbo em Adultos/enzimologia , Chumbo/análise , Transtornos Mentais/epidemiologia , Polimorfismo Genético , Sintase do Porfobilinogênio/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Exposição Ambiental/análise , Predisposição Genética para Doença , Genótipo , Humanos , Chumbo/sangue , Estudos Longitudinais , Masculino , Massachusetts/epidemiologia , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Patela/química , Análise de Regressão , Inquéritos e Questionários , Tíbia/química
13.
Environ Health Perspect ; 115(12): 1696-700, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18087585

RESUMO

BACKGROUND: Pulse pressure increases with age in industrialized societies as a manifestation of arterial stiffening. Lead accumulates in the vasculature and is associated with vascular oxidative stress, which can promote functional and structural vascular disease. OBJECTIVES: We tested the hypothesis that cumulative community-level lead exposure, measured with K-X-ray fluorescence, is associated with pulse pressure in a cohort of adult men. METHODS AND RESULTS: In a cross-sectional analysis of 593 men not treated with antihypertensive medication, tibia lead was positively associated with pulse pressure (p < 0.001). Adjusting for age, race, diabetes, family history of hypertension, education, waist circumference, alcohol intake, smoking history, height, heart rate, fasting glucose, and total cholesterol-to-HDL ratio, increasing quintiles of tibia lead remained associated with increased pulse pressure (ptrend = 0.02). Men with tibia lead above the median (19.0 microg/g) had, on average, a 4.2-mmHg (95% confidence interval, 1.9-6.5) higher pulse pressure than men with tibia lead level below the median. In contrast, blood lead level was not associated with pulse pressure. CONCLUSIONS: These data indicate that lead exposure may contribute to the observed increase in pulse pressure that occurs with aging in industrialized societies. Lead accumulation may contribute to arterial aging, perhaps providing mechanistic insight into the observed association of low-level lead exposure with cardiovascular mortality.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Exposição Ambiental , Intoxicação por Chumbo , Características de Residência , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/efeitos dos fármacos , Estudos de Coortes , Humanos , Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Tíbia/química
14.
Environ Health Perspect ; 115(8): 1154-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17687441

RESUMO

BACKGROUND: Lead exposure and psychological stress have been independently associated with hypertension in various populations, and animal studies suggest that when they co-occur, their effects may be exacerbated. OBJECTIVES: We examined whether psychological stress modifies the impact of cumulative lead exposure (measured as bone lead levels) on hypertension and blood pressure in Boston-area community-exposed men participating in the Normative Aging Study. METHODS: We evaluated the modifying effect of stress on lead exposure on baseline hypertension status (513 participants) and on blood pressure in those without hypertension (237 participants), cross-sectionally. In baseline nonhypertensives, we examined the same risk factors in relation to prospective risk of developing hypertension. RESULTS: Cross-sectional analysis revealed a positive interaction between stress and tibia lead on systolic blood pressure, after adjusting for age, body mass index, family history of high blood pressure, education, smoking, alcohol consumption, physical activity, and nutritional factors. In prospective multivariate analyses, high stress also modified the effect of tibia lead and patella lead on the risk of developing hypertension. Those reporting high stress had 2.66 [95% confidence interval (CI), 1.43-4.95] times the risk of developing hypertension per standard deviation increase in tibia lead and had 2.64 (95% CI, 1.42-4.92) times the risk per standard deviation increase in patella lead. CONCLUSION: To our knowledge, these are the first analyses to look at interactive effects of stress and lead on hypertension in humans. These results suggest that the effect of lead on hypertension is most pronounced among highly stressed individuals, independent of demographic and behavioral risk factors.


Assuntos
Poluentes Ambientais/análise , Hipertensão/etiologia , Chumbo/análise , Patela/química , Estresse Psicológico/complicações , Tíbia/química , Envelhecimento/metabolismo , Pressão Sanguínea , Boston/epidemiologia , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Humanos , Hipertensão/epidemiologia , Hipertensão/metabolismo , Chumbo/toxicidade , Masculino
15.
Environ Health Perspect ; 115(8): 1210-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17687449

RESUMO

BACKGROUND: As iron and lead promote oxidative damage, and hemochromatosis (HFE) gene polymorphisms increase body iron burden, HFE variant alleles may modify the lead burden and cognitive decline relationship. OBJECTIVE: Our goal was to assess the modifying effects of HFE variants on the lead burden and cognitive decline relation in older adults. METHODS: We measured tibia and patella lead using K-X-ray fluorescence (1991-1999) among participants of the Normative Aging Study, a longitudinal study of community-dwelling men from greater Boston. We assessed cognitive function with the Mini-Mental State Examination (MMSE) twice (1993-1998 and 1995-2000) and genotyped participants for HFE polymorphisms. We estimated the adjusted mean differences in lead-associated annual cognitive decline across HFE genotype groups (n = 358). RESULTS: Higher tibia lead was associated with steeper cognitive decline among participants with at least one HFE variant allele compared with men with only wild-type alleles (p interaction = 0.03), such that a 15 microg/g increase in tibia lead was associated with a 0.2 point annual decrement in MMSE score among HFE variant allele carriers. This difference in scores among men with at least one variant allele was comparable to the difference in baseline MMSE scores that we observed among men who were 4 years apart in age. Moreover, the deleterious association between tibia lead and cognitive decline appeared progressively worse in participants with increasingly more copies of HFE variant alleles (p-trend = 0.008). Results for patella lead were similar. CONCLUSION: Our findings suggest that HFE polymorphisms greatly enhance susceptibility to lead-related cognitive impairment in a pattern consistent with allelelic dose.


Assuntos
Transtornos Cognitivos/genética , Poluentes Ambientais/análise , Antígenos de Histocompatibilidade Classe I/genética , Chumbo/análise , Proteínas de Membrana/genética , Patela/química , Tíbia/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores/análise , Boston/epidemiologia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/metabolismo , Genótipo , Proteína da Hemocromatose , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Escalas de Graduação Psiquiátrica
16.
Environ Health Perspect ; 115(6): 871-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17589593

RESUMO

BACKGROUND: Lead exposure has been associated with higher blood pressure, hypertension, electrocardiogram abnormalities, and increased mortality from circulatory causes. OBJECTIVE: We assessed the association between bone lead-a more accurate biomarker of chronic lead exposure than blood lead-and risk for future ischemic heart disease (IHD). METHODS: In a prospective cohort study (VA Normative Aging Study), 837 men who underwent blood or bone lead measurements at baseline were followed-up for an ischemic heart disease event between 1 September 1991 and 31 December 2001. IHD was defined as either a diagnosis of myocardial infarction or angina pectoris that was confirmed by a cardiologist. Events of fatal myocardial infarction were assessed from death certificates. RESULTS: An IHD event occurred in 83 cases (70 nonfatal and 13 fatal). The mean blood, tibia, and patella lead levels were higher in IHD cases than in noncases. In multivariate Cox-proportional hazards models, one standard deviation increase in blood lead level was associated with a 1.27 (95% confidence interval, 1.01-1.59) fold greater risk for ischemic heart disease. Similarly, a one standard deviation increase in patella and tibia lead levels was associated with greater risk for IHD (hazard ratio for patella lead = 1.29; 95% confidence interval, 1.02-1.62). CONCLUSIONS: Men with increased blood and bone lead levels were at increased risk for future IHD. Although the pathogenesis of IHD is multifactorial, lead exposure may be one of the risk factors.


Assuntos
Chumbo/análise , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Patela/química , Tíbia/química , Idoso , Estudos de Coortes , Humanos , Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estados Unidos/epidemiologia , Veteranos
17.
Zhongguo Fei Ai Za Zhi ; 10(6): 495-9, 2007 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-21129307

RESUMO

BACKGROUND: Neoadjuvant chemotherapy is one of the hot points of lung cancer therapy,which has been proven to be able to improve resection rate and 5-year survival of patients.But its effect on operation safety is not clear yet.The aim of this study is to confirm the effect of neoadjuvant chemotherapy on pulmonary arterial wall so as to assess its safety for operation in patients with lung cancer. METHODS: Thirty-two patients underwent lobectomy or pneumonectomy with mediastinal lymphadenectomy after a neoadjuvant chemotherapy,compared with 36 patients surgically treated only.During the operation,the changes of thoracic structure were observed.After the operation,the pulmonary artery specimens were detected pathologically. RESULTS: The incidence of pleural fibrosis and thickening of pulmonary arterial tunica adventitia in neoadjuvant chemotherapy group was significantly higher than those of control group(59.38% vs 22.22%,P < 0.01;68.75% vs 19.44%,P < 0.01).The incidence of tunica intima,internal elastic membrane and tunica media damage in neoadjuvant chemotherapy group was also markedly higher than those of control group(65.62% vs 33.33%,P < 0.01;59.38% vs 19.44%,P < 0.01;71.88% vs 22.22%,P < 0.01). CONCLUSIONS: Neoadjuvant chemotherapy may lead to pleural fibrosis and thickening of pulmonary arterial tunica adventitia and increase crispness of pulmonary arterial wall,which may increase difficulty and risk of operation.

18.
Environ Health Perspect ; 114(11): 1718-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17107858

RESUMO

BACKGROUND: Altered heart rate variability (HRV), a marker of poor cardiac autonomic function, has been associated with sudden cardiac death and heart failure. OBJECTIVE: We examined the association of low-level lead exposure measured in bone by K-X-ray fluorescence with alterations in HRV, and whether metabolic syndrome (MetS) or its individual components modify those associations. METHODS: HRV measures [power in high-frequency (HFnorm) and low-frequency (LFnorm) in normalized units, and LF/HF] were taken among 413 elderly men from the Normative Aging Study. MetS was defined as subjects having three or more of the following criteria: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein, high blood pressure, and high fasting glucose. RESULTS: Of the subjects, 32% were identified as having MetS. Inverse but nonstatistically significant associations of both tibia and patella lead levels with HFnorm and nonstatistically significant positive relations with LFnorm and LF/HF were found in the entire cohort. There was a graded, statistically significant reduction in HFnorm and increases in LFnorm and LF/HF in association with an increase in patella lead as the number of metabolic abnormalities increased. We also observed that higher patella lead was consistently associated with lower HFnorm and higher LFnorm and LF/HF among subjects with MetS or its individual components. No statistically significant interaction between MetS and tibia lead was observed. CONCLUSION: The results suggest that elderly men with MetS were more susceptible to autonomic dysfunction in association with chronic lead exposure as measured in patella. The modification by MetS is consistent with a role for oxidative stress in lead toxicity on the cardiovascular system.


Assuntos
Poluentes Ambientais/toxicidade , Cardiopatias/etiologia , Chumbo/toxicidade , Síndrome Metabólica/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Exposição Ambiental/efeitos adversos , Cardiopatias/epidemiologia , Cardiopatias/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Estresse Oxidativo , Patela/química , Estados Unidos , United States Department of Veterans Affairs , Veteranos
19.
J Biochem ; 139(4): 725-31, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16672273

RESUMO

Trichosanthin is the active protein component in the Chinese herb Trichosanthes kirilowi, which has distinct pharmacological properties. The cytotoxicity of trichosanthin was demonstrated by its selective inhibition of various choriocarcinoma cells. When Jar cells were treated with trichosanthin, the influx of calcium into the cells was observed by confocal laser scanning microscopy. When the distribution of trichosanthin-binding proteins on Jar cells was studied, two classes of binding sites for trichosanthin were shown by radioligand binding assay. Furthermore, the cytoplasmic membrane of Jar cells was biotinylated and the trichosanthin-binding proteins were isolated with trichosanthin-coupled Sepharose beads. Two protein bands with molecular masses of about 50 kDa and 60 kDa were revealed, further characterization of which should shed light on the mechanism of the selective cytotoxicity of trichosanthin to Jar cells.


Assuntos
Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Tricosantina/metabolismo , Animais , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/toxicidade , Biotinilação , Cálcio/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/química , Sobrevivência Celular/efeitos dos fármacos , Coriocarcinoma/metabolismo , Coriocarcinoma/patologia , Coriocarcinoma/ultraestrutura , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Immunoblotting , Microscopia Confocal , Proteínas de Plantas/metabolismo , Proteínas de Plantas/toxicidade , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tricosantina/toxicidade , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia , Neoplasias Uterinas/ultraestrutura
20.
Phys Med Biol ; 51(2): 351-60, 2006 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-16394343

RESUMO

A new 109Cd gamma-ray induced K-XRF bone lead measurement system using an array of four detectors has been developed. Previous results from Monte Carlo (MC) simulations and experiments with phantoms predicted that it would be about three times more sensitive than the conventional system, albeit using a more active source. A dosimetry study has been performed for this system and it demonstrated that the dose delivered to the measured individuals is acceptable even for 5-year-old children. Approval to apply this system to human studies has been received from the Research Ethics Board. In this study, 20 adult volunteers, 10 male, 10 female, were recruited to have their tibia measured with both the conventional system and the new system. The result confirmed the improvement predicted by the MC simulations and the in vitro measurements. Two other interesting points were discovered from the data. One is that the data from the new system showed a significant positive correlation between age and tibia lead concentration, while the data from the conventional system do not. The other is that 85% of the tibia lead concentrations were under the minimum detection limit when measured by the conventional system, and the proportion reduced to 50% when measured by the new system.


Assuntos
Radioisótopos de Cádmio , Raios gama , Chumbo/análise , Método de Monte Carlo , Tíbia/química , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Radiografia , Tíbia/diagnóstico por imagem
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